class Animail:
    def say_who(self):
        print("我是动物")
        pass
    pass
class Cat(Animail):
    def say_who(self):
        print("我是猫")
        pass
    pass
class Dog(Animail):
    def say_who(self):
        print("我是狗")
        pass
    pass
class Pig(Animail):
    def say_who(self):
        print("我是猪")
        pass
    pass
class Duck(Animail):
    def say_who(self):
        print("我是鸭子")
        pass
    pass
class Tiger(Animail):
    def say_who(self):
        print("我是老虎")
        pass
    pass
class Person(Animail):
    def say_who(self):
        print("我是人")
        pass
    pass
list1=[Cat(),Duck(),Dog(),Pig(),Tiger(),Person()]
def intruduce(o):
    for item in o:
        item.say_who()
    pass
intruduce(list1)

